A conventional superlattice castellated field effect transistor (SLCFET) device includes superlattice castellations or ridges having lengths sized to be much larger than a length of a gate of the device. Deposition of gate metal divides the castellations into a channel region directly under the gate, flanked on either side by source and drain access regions whose lengths vary depending on an alignment of the gate to the castellations. These variations are undesired and have an adverse impact on device performance.